I. Field
The present disclosure relates generally to wireless communications and more specifically to enhanced uplink (EUL) communications.
II. Background
Wireless communication systems are widely deployed to provide various types of communication content such as, for example, voice, data, and so on. Typical wireless communication systems may be multiple-access systems capable of supporting communication with multiple users by sharing available system resources (e.g., bandwidth, transmit power, . . . ). Examples of such multiple-access systems may include code division multiple access (CDMA) systems, time division multiple access (TDMA) systems, frequency division multiple access (FDMA) systems, orthogonal frequency division multiple access (OFDMA) systems, and the like. Additionally, the systems can conform to specifications such as third generation partnership project (3GPP), 3GPP long term evolution (LTE), ultra mobile broadband (UMB), etc., and can use one or more protocols, such as high-speed downlink packet access (HSDPA), single carrier HSDPA (SC-HSDPA), dual carrier HSDPA (DC-HSDPA), etc.
Generally, wireless multiple-access communication systems may simultaneously support communication for multiple mobile devices. Each mobile device may communicate with one or more access points (e.g., base stations, femtocells, picocells, relay nodes, and/or the like) via transmissions on forward and reverse links. The forward link (or downlink) refers to the communication link from access points to mobile devices, and the reverse link (or uplink) refers to the communication link from mobile devices to access points. Further, communications between mobile devices and access points may be established via single-input single-output (SISO) systems, multiple-input single-output (MISO) systems, multiple-input multiple-output (MIMO) systems, and so forth. In addition, mobile devices can communicate with other mobile devices (and/or access points with other access points) in peer-to-peer wireless network configurations.
In some 3GPP releases, mobile devices utilize enhanced uplink (EUL) in communicating with access points for increased efficiency and capability. In this regard, mobile devices can select/reselect cells by transmitting radio resource control (RRC) connection setup requests to related access points, receiving common enhanced dedicated channel (E-DCH) resources from the access points, and utilizing the E-DCH resources to communicate to the access points within the cells. Access points can additionally provide an enhanced radio network temporary identifier (E-RNTI) to the devices along with the E-DCH resources, and the devices can specify the E-RNTI in subsequent communications to facilitate identification.
EUL additionally provides enhanced random access in connected mode where upon receiving E-DCH resources from an access point (such as a dedicated control channel (DCCH)), a mobile device can communicate general data over the control resources without first setting up a traffic channel. To facilitate such communication, the mobile device can specify the received E-RNTI within the general data sent over the resources. This allows the access point to identify the mobile device and associate the general data communication therewith. Additionally, to facilitate efficient mobility, mobile devices can travel over a service area in one or more connected mode states, such as cell forward link access channel (CELL_FACH), cell dedicated channel (CELL_DCH), cell paging channel (CELL_PCH), and universal terrestrial radio access network (UTRAN) registration area paging channel (URA_PCH), each having different procedures with respect to maintaining connection to the access point or underlying wireless network.